In-Pixel temperature sensors with an accuracy of ±0.25 °C, a 3σ variation of ±0.7 °C in the spatial domain and a 3σ variation of ±1 °C in the temporal domain

Research output: Contribution to journalArticleScientificpeer-review

3 Downloads (Pure)

Abstract

This article presents in-pixel (of a CMOS image sensor (CIS) temperature sensors with improved accuracy in the spatial and the temporal domain. The goal of the temperature sensors is to be used to compensate for dark (current) fixed pattern noise (FPN) during the exposure of the CIS. The temperature sensors are based on substrate parasitic bipolar junction transistor (BJT) and on the nMOS source follower of the pixel. The accuracy of these temperature sensors has been improved in the analog domain by using dynamic element matching (DEM), a temperature independent bias current based on a bandgap reference (BGR) with a temperature independent resistor, correlated double sampling (CDS), and a full BGR bias of the gain amplifier. The accuracy of the bipolar based temperature sensor has been improved to a level of ±0.25 °C, a 3σ variation of ±0.7 °C in the spatial domain, and a 3σ variation of ±1 °C in the temporal domain. In the case of the nMOS based temperature sensor, an accuracy of ±0.45 °C, 3σ variation of ±0.95 °C in the spatial domain, and ±1.4 °C in the temporal domain have been acquired. The temperature range is between-40 °C and 100 °C.

Original languageEnglish
Article number665
Number of pages16
JournalMicromachines
Volume11
Issue number7
DOIs
Publication statusPublished - Jul 2020

Keywords

  • CMOS image sensor
  • Dark current
  • In-pixel temperature sensors
  • Tixel

Fingerprint Dive into the research topics of 'In-Pixel temperature sensors with an accuracy of ±0.25 °C, a 3σ variation of ±0.7 °C in the spatial domain and a 3σ variation of ±1 °C in the temporal domain'. Together they form a unique fingerprint.

  • Cite this